Sign of the Times

Schools are back in session, and if there's one lesson that transportation engineers want drivers to learn, it's to pay attention while driving in construction zones. That's why Dr. Ghulam Bham, assistant professor of civil, architectural and environmental engineering at Missouri S&T, and his students are studying the effectiveness of dynamic variable message signs that are often used in highway work zones.

When used effectively, these devices provide motorists with real-time information about current traffic conditions, such as traffic congestion or reduced speeds. The messages displayed are automated and based on data collected by sensors that are placed alongside the road.

The signs are common sights to motorists who travel on Interstate 44 in Missouri. For example, the signs were recently used in construction zones near Lebanon and Richland while the Gasconade River bridge, built in 1955, underwent an overhaul.

"We are evaluating drivers' perceptions of the signs," Bham says. "In addition to collecting video data and sensor information, we conducted a survey of 100 passenger and truck drivers who had stopped at a nearby gas station."

Last year, more than 2,500 vehicles were involved in work zone crashes in the St. Louis area. Eight people died during those crashes and many more were injured. According to the Missouri Department of Transportation, most of the crashes in work zones were rear-end crashes, which usually indicates that one or more vehicles crashed into stopped or slowed traffic ahead.